Anne,

I have noticed this behaviour too, especially when trying to import 3ds models. Probably there are several "dialects" in the "3ds language", some of which aren't correctly translated when importing the model into SH3D.

There may be a solution for your problem: import these 3ds models into Blender, then from Blender export them in OBJ format. You may have to experiment a bit with the export settings: there are quite a few options, and I'm not a Blender specialist.

Hans